Brake



Sept. 22, 1931. 1 SNE-ED 1,824,510

BRAKE Filed Sept. 12', 1927 gnou/toc Maw @fm/MLL Panarea sept. ,22, v1931 UNITED STATES .rome sNEEn, or DETROIT, urcmoamassmnon To THE Minn-AND STEEL rizonuo'rs ,PATENT OFFICE olPANY, 0F CLEVELAND, GEIQ, A. CORPORATION OHIO BEAU Application `allied 'September 12, 1927. Serial No. 218,873.

This invention relates to brakes and particularly to the type -adapted for use o n motor vehicles.

It is among the objects of my invention to construct a brake which-Will be equally effective re ardless of the direction of drum rotation. ther objects include provisions for a self-energizing eect in the operation of the brake. Another object is to provide a unique anchorage and connections and adjustments therewith, which 'shall compensate for wear and modify the characteristic of the brake within certain limits. Another object is to provide. a. brake shoe having characteristics of ilexibility and rigidity, which lend themselves to the other features of my invention.

on Fig. 1.

Other objects will appear from the following description of my invention, a preferred form of which is shown in the accompanying drawings. Theessential characteristlcs are summarized in the claims.

In the drawings, Fi 1 discloses a general la out of the bra e mechanism; and Fig. 2 1s a section taken along the line 2--2 Referring particularly to Fig. `1, D represents the usual brake drum inwhich the shoe 10 is mounted. The shoe 10 may comprise a lining su porting portion 11 and may have inwar l extending radial side flanges 12 at the a jacent ends of the shoe, and similarly ormed flanges 14 in the midportion of the shoe. Suitable lining L is carried by the shoe. A conventional floating cam C is disposed between the free ends' of the shoe and ymay be mounted on a suitable shaft which may4 be rotated in the usual manner by' means not shown. The side flanges 12 in the ends of the shoe may be inturned to form acam engaging surface as at 13. A retraction spring 24 is shown to draw the ends of the shoe against the cam.

Referring also to Fig. 2, I show the midportion or bottom portion of the shoe chan.- nelled in cross section with the side flanges 14 as mentioned above. These side flan es have a pair of'aligned openings `30 and 3 A relation to the drum may be changed by partial rotation by either or both of the anchorpins. A spring 2l extends from the mid-portion of the shoe to the backing plate and raises the shoe upwardly keeping the links in engagement with the anchor pins and maintaining the shoe normally out of contact with `the drum.

`In operation, supposing the rotation of the drum to be clockwise, the ends of the shoe are spread by the cam until an initial contact is made with the drum, whereupon the shoe is urged circumferentially in a clockwise direction. The links 32 and 32A having been in contact with anchor pins 35 and 35A because of the tension of the spring 21,- are no'w moved accordingto the move- :nent of the shoe. That is, the link 32A is drawn downwardly away' from the anchor pin, whereas the link 32 is merely swung around the anchor pin 35 as a center. p The pin 30 describes an arc and carries the'midportion of the shoes radially in that arc. In this manner the whole mid-portion of the shoe is forced to contact with the drum and the free end of the shoe on the ri ht, as

viewed in Fig. 1, acts as a servo shoe or the mid-portion of .the shoe. It will be noted that the ends of the shoes and the mid-portion are comparatively rigid by reason of the reinforcing flanges but between these portions are comparatively flexible portions F, F so that the ends are free to move relative to the mid-portion. A self-energizing or servo effect is 'ven to substantially two-thirds ofthe W ole shoe in each operation.

In the form of my invention shown herewith, I have positioned the anchor pins substantially 120 trom each other. The middle flexible portions F, F o the shoe occupy small arcs and are disposed within about 100 of.\the end of the shoe so that the distancesffrom the one end of the shoe around to theopposite end of the flange 14 or to the most remote end of the rigid middle portion of the shoe, is substantially 250. Since the reinforced or channelled mid-portion of the shoe moves in a body when it is urged into engagement, it will be seen that in operation substantially 250 of friction surface is brought into operation by the servo action whenever the brake is applied.

From the foregoing, it will appear that I have provided a hi hly eliicient brake which will be equally e ective regardless of the direction of drum rotation and which has inherent in its construction a modified selfenergizing eil'ect. Various modiiications in form and degree will occur to one skilled in the art, and while I have shown a preferred form of my invention, I do not care to be limited in the scope thereof other than by the claims appended hereto.

I claim: v l

1. In abrake, the combination of a drum, a pair of anchor pins spaced apart, relatively rigid friction means spaced between said anchor vpins, a link ivoted to said friction means and engageab e with one of said pins when the drum rotation is clockwise, a second link pivoted to said friction means and enga eab e with the other. of said pins when the rum'rotation is counter clockwise, and

additional relatively flexible friction means angularly dispacedbeyond said anche;- pins and adapted to serve said rst named means regardless of the direction of drum rotation.

2. In a brake, the combination of a substantially'annular brake shoe having a comparatively ri id middle portion, a brake drum, expan ing means disposed between the ends of the shoe, an anchorv pin, a link pivotally mountedin the said ri 'd portion of the shoeand having a pivota and slid. able enga ement with said pin. s

3. In a rake, the combination of a brake drum, a substantially` annular' brake shoe, expandin means disposed between the adjacent en s of the shoe,l said 'shoe being relatively rigidthroughout that portion opposite said expanding means and having ilexible parts between the ends and the said rigid portion, anchor pins spaced from each other and adjacent the extremities of-said rigid portion, and means connecting said rigid portion `of the shoe to said anchor pins, whereby one or the other of said pins take A the braking torque depending upon the' direction of drum rotation, said means comprising a pair of links divergin'g from themedian line ofthe brake and connected 'to said rigid portion of the shoe at their near .ends

05 and engaging the anchors at their far ends.

'tremities -of said relative 4radial side flanges, sai

4. In a brake, the combination of a brake drum, a brake shoe, said brake shoe being formed as asplit ring 'with a relatively rigid middle portion and with relatively flexible portions adjacent thereto, and 'means for ancho-ring said shoe at oints near the exrigid middle portion, said means comprising a pair of l1nks pivotally mounted in said rigid `middle portion at symmetrically spaced points relative to said rigid middle portion and engageable with anchoring means.

5. In a brake, the combination of a. brake drum, a brake shoe, said brake shoe being formed as a split ring with relatively rigid end portions and a relatively rigid middle portion opposite said end portions and with relatively flexible portions 'symmetrically disposed therebetween, and means for anchoring said shoe at points near the extremities of said relatively rigid middle portion, comprising links pivotally supported in spaced parts of said middle rigid ortion and extending in divergence to eac other to en agement with anchoring means.

6. n a brake, the .combination of an anchor pin, a substantiall annular' brake 'shoe having a relatively rigid middle p0rtion ehannelled in cross section and havin inwardly extending radial side flanges, sai side flanges having a pair of aligned openings, a pin journalled in said openings, and a link carried by said pin and engagmg said anchor.

7 A brake having a pair of anchor pins.l a brake shoe com rising relativel lexible and relativelytrigid) port1ons, one o the relatively rigid portions being channelled in cross section and having inwardly extending iside flanges having two pair of aligned openings symmetrically disposed with relation to the ends of said shoe andto the vertical axis of the brake and havinga pair of pins mounted4 in said openings for connecting said shoe with symmetrically disposed anchors, and links carried by said pins andA engaging said anchora l8. .A brake com risin a xed supporting part, a drum, are ative y rigid shoe part, a i

pair of spacedA anchors carriedv by the fixed supporting part, a pair of links each pivotally mounted in the shoe part and at o posite ends thereof and inclined away rom each other and having pivotal and slidable brake comprising a fixed supporting.

a pair of anchors -carried by said fixed supporting part and disposed generally adjasignature.

JOHN SNEED.l 

